Virtuoso SPARQL Query Editor | Sponge

How To Enable Sponge?

When a new Virtuoso server is installed, the default security restrictions do not allow SPARQL endpoint users to retrieve remote RDF data.
To remove this restriction, the DBA should grant "SPARQL_SPONGE" privilege to "SPARQL" account.
If you are the Database Administrator and want to enable this feature, you can perform the following steps: